Apparatus for hydro-thermical treatment of starchy products, in particular rice

Abstract

For the production of parboiled rice or a similar starch-containing product, the rice, after conveniently being moisted in a preheating installation 1, is brought to boiling temperature and, having reached this, is kept at this boiling temperature in a heat-retaining vessel 9 until the cooking process is finished. Thereupon, the rice is dried in a drying installation 12 and cooled, if necessary.

What is claimed is: 
     
       1. An apparatus for hydro-thermically treating a starch containing product, comprising boiling means for boiling said starch containing product, said boiling means including boiling vessel means for holding said product,   heat supply means for supplying heat to said boiling vessel means, and being operative to bring the product up to boiling temperature,   heat retaining vessel means separate from said boiling means and operatively connected to said boiling means for receiving said product from said boiling means and for maintaining said product at boiling temperature during a predetermined period, said heat retaining vessel means including tubing through which a heat transfer medium can flow for conducting heat to said product while in the heat retaining vessel means, said heat retaining vessel means having an outlet region,   nozzles disposed in said boiling means for injecting steam into said product, and   drying means connected to the outlet region of said heat retaining vessel means for drying the product after boiling by said boiling means, said outlet region of said heat retaining vessel means being located adjacent said drying means.   
     
     
       2. Apparatus as claimed in claim 1, wherein said product is rice. 
     
     
       3. Apparatus as claimed in claim 1, further comprising cooling means operatively coupled to said drying means for cooling the product. 
     
     
       4. Apparatus as claimed in claim 1, wherein said heat retaining vessel means forms a passageway for allowing continuous passage of said product through the passageway. 
     
     
       5. Apparatus as claimed in claim 1, wherein said tubing in said heat retaining vessel means serves as heating means to compensate for natural heat losses during said predetermined period. 
     
     
       6. Apparatus as claimed in claim 1, wherein said heat retaining vessel means has a passage arranged in vertical direction to allow feeding of said product by gravity. 
     
     
       7. Apparatus as claimed in claim 1, wherein said heat retaining vessel means forms a passageway for allowing continuous passage of said product in a predetermined direction of flow, and said drying means comprises a drying element connected to said heat retaining vessel means in the direction of flow to form part of said end region, and   blowing means for blowing drying air through said drying element.   
     
     
       8. Apparatus as claimed in claim 7, wherein said blowing means is arranged for blowing drying air across the direction of flow of said product. 
     
     
       9. Apparatus as claimed in claim 1, wherein said heat retaining vessel means forms a passageway for allowing continuous passage of said product in a predetermined direction of flow, and said drying means comprises a dryer being separately arranged from said heat retaining vessel means and,   blowing means for blowing drying air through said dryer in counter-direction to said direction of flow of said product.   
     
     
       10. Apparatus as claimed in claim 1, further comprising discharging means arranged within said outlet region of said heat retaining vessel means for providing dosed discharge of said product. 
     
     
       11. An apparatus for hydrothermally treating a starch containing product, comprising boiling vessel means for boiling said starch containing product, said product being contained within said boiling vessel means during boiling of said product,   heat retaining vessel means operatively connected to said boiling vessel means for receiving said product in a boiled state from said boiling vessel means and for maintaining the product at a boiling temperature during a predetermined period,   drying means connecting with an end region of said heat retaining vessel means for drying the product upon passage of the product through said heat retaining vessel means,   heating means for said heat retaining vessel means,   wherein said heat retaining vessel means forms a passageway for allowing continuous passage of said product in a predetermined direction of flow, and said heating means comprises   a plurality of tubings extending within said heat retaining vessel means in a direction across said direction of flow, and   source means for a heat carrier medium connected to said tubings, said tubings being adapted to permit said heat carrier medium to flow through said tubings and transfer heat to said product.   
     
     
       12. Apparatus as claimed in claim 11, wherein said heat carrier medium is steam. 
     
     
       13. Apparatus as claimed in claim 11, wherein said tubings have an elongated cross-section extending in said direction of flow, said cross-section comprising a roof portion tapering off against said direction of flow by a predetermined angle and having a predetermined length measured in said direction of flow, and   an adjacent portion having a length longer than said predetermined length.   
     
     
       14. Apparatus as claimed in claim 13, wherein said adjacent portion tapers off by an angle being more acute than said predetermined angle. 
     
     
       15. Apparatus as claimed in claim 11, wherein said heat retaining vessel means consists of at least a first and a second adjacent module forming a passageway for said product, said tubings being parallel to one another in each of said modules, said tubings of said first module running in a direction across the direction of the tubings of said second module. 
     
     
       16. Apparatus as claimed in claim 15, wherein the direction of said tubings of adjacent modules form an angle of 90°.